> 12 °
Level IV studie: Combined HTO, ACLR and CR is an effective treatment in these cases. The graft failure rate increases with an increase in tibial slope, in particular when exceeding 12.5°.
There was no significant difference between PTS measurements that used the proximal anatomic axis from lateral knee radiographs and those that used the anatomic axis from full-length lateral tibia radiographs:
Posterior Tibial Slope Measurements Using the Anatomic Axis Are Significantly Increased Compared With Those That Use the Mechanical Axis. LaPrade M.D., Ph.D. Arthroscopy: The Journal of Arthroscopic and Related Surgery, 2021-01-01, Volume 37, Issue 1, Pages 243-249